Word: quartz
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Strong, Sensitive Scale. The most accurate chemist's scales, those that use quartz fibers as springs, can weigh only tiny quantities. Scales big enough to handle good-sized samples are not nearly as sensitive. Last week Dr. Alsoph H. Corwin of Johns Hopkins University told about a scale that he has developed which is both strong and sensitive. Its beam teeters on a finely polished knife edge of boron carbide (almost as hard as diamond), resting on the same material. The edge is so sharp that the pressure on its minute bearing surface...
...world's Easter gifts, few are as lavish as the bejeweled eggs passed out by Russia's rich and royal in the time of the czars. The smaller eggs-delicate trinkets of gold and enamel, flawless rose quartz, pearls and diamonds-were the gifts of Russia's wealthy classes; the largest and costliest eggs were reserved for the reigning Romanovs. Three handsome examples (opposite) are the gold and lapis lazuli egg, with a miniature portrait of Czarevitch Alexis, given by Nicholas II to his Czarina in 1912; the fabulous rock crystal egg (at top), which contains...
...from Ottawa's National Museum, scrambled up the rocky slope on Lake Huron's Canadian shore to have a look. Half an hour later, he was poking and prodding one of the richest diggings in North America. The forest floor was dotted with crude knives, scrapers, and quartz chips. "I felt drunk," he said. "It looked as though the Indians had heard me coming, dropped everything, and run into the bush...
...means had been developed before to polarize light, but it involved the use of quartz crystals, which were arranged so that the crystal lattice was aligned along one axis. Light would be transmitted freely by one axis of the crystals, but it would be blocked entirely by the other axis. This worked--in theory. But in practice, a perfect alignment of the crystals was impossible, and their sizes made the apertures through which light passed comparatively small...
Many substances, including platinum give off ions (electrified particles) when heated to high temperature. At one end of the lonophone's quartz tube is a small quartz cylinder with a coating that contains fine particles of platinum. When the platinum is heated electrically to about 1,000° C., it fills the horn-shaped cavity above it with a cloud of rapidly zigzagging ions. The ion cloud responds almost instantly to changes in the strength of a high-frequency electric field around the little quartz cylinder, and the cloud's expansion and contraction set up sound waves. When...